1. Field of the Invention
The present invention relates to a device for holding a ceramic substrate or other substrate made of a fragile material, for mounting an electric or electronic component onto the substrate, for applying an adhesive into a desired spot or spots of the substrate, or for other purpose. The invention also relates to a process of fabricating an electric circuit by using such a holding device.
2. Discussion of Related Art
There is known an operation for fabricating a printed circuit substrate or other electric circuit, by mounting electric components onto a circuit substrate such as a printed wiring board. Such a fabricating operation is commonly carried out by using a substrate work system equipped with a substrate holding device for holding the circuit substrate, a working head for achieving an operation in a predetermined portion of the circuit substrate held by the substrate holding device, and a relative movement device for moving the substrate holding device and the working head relative to each other. As such a substrate work system, there is known an adhesive applying system and an electric-component mounting system, for example. In the adhesive applying system, the working head takes the form of an applying head for applying an adhesive to the circuit substrate. In the electric-component mounting system, the working head takes the form of a mounting head for mounting the electric component onto the circuit substrate.
It is common that the above-described substrate working system is equipped with a substrate clamping device which includes a metallic receiving member and a metallic movable member adapted to force a peripheral or other portion of the circuit substrate against the receiving member, for thereby clamping the circuit substrate. However, it is not easy to clamp the circuit substrate in an appropriate manner, particularly, where the circuit substrate is provided by a fragile-material-made substrate such as a ceramic substrate made principally of a ceramic material. The ceramic material or other fragile material is likely to be broken or damaged with substantially no plastic deformation, if a large force or stress is applied to the circuit substrate. Therefore, where the circuit substrate is convexed, the circuit substrate is likely to be damaged if the circuit substrate is intended to be straightened by forcing the circuit substrate to be deformed in an amount too large for its elastic deformability. Further, there is a possibility that the circuit substrate might be damaged if the circuit substrate receives an excessively large load, for example, due to a shock generated when the circuit substrate is forced by the movable member against the receiving member.